John barky



(N0 Model.)

J. BARRY. Thermometer Tube.

No. 233,963. Patented Nov. 2, 1880.

l [2F E JJJUHMTU Wzesses N.FETER8. FHcTmLITMoGRAPl-IER. WASHINGTQN D C UNITED STATES PATENT OFFICE.

JOHN BARRY, OF NEW YORK, N. Y.

THERMOMETER-TUBE.

SPECIFICATION forming part of Letters Patent No. 233,963, dated November 2, 1880. Application filed September 17, 1880. (No model.)

To all whom it may concern Be it known that I, JOHN BARRY, of the city and county of New York, in the State of New York, have invented a certain new and useful Improvement in Thermometers, of which the following is a specification.

My invention relates particularly to clinical and chemical thermometers having a tine bore; and the object is to enable the height of mercuryor fluid in the bore to be more easily seen, and at the same time to protect the thermometer tube and prevent the black on the engraved scale from being defaced.

To this end the invention consists in a glass jacket for a thermometer-tube having' a greater thickness upon one side, so as to produce a rounded protubcrance of lens-like character upon its exterior, which serves to magnify the column of mercury or fluid and render it more prominent.

It also consists in the combination, with athermometer-tube of cylindric form, ot'a jacket of the kind above described fitted and secured outside the tube.

In the accompanying drawings,- Figure l represents a side view of a thermometer tube and jacket embodying my invention. Fig. 2 represents an'exterior view of the tube and jacket detached one from the other; and Fig. 3 represents a transverse section ot' the tube and jacket when together, upon a larger scale.

Similar letters ot' reference designate corresponding parts in allthe figures.

A designates a thermometertube ot' cylindric form, or at least having the portion upon which is marked the scale of cylindric form, and which is no Wise different from the clinical and chemical thermometer tubes now employed.

B designates a glass jacket having a bore of cylindric or other` form corresponding with the exterior of the thermometer-tube, and of sufficient size to enable it to be readily slipped over the said tube A. Upon the exterior ot' this jacket is a rounded protuberance, B', of lens-like character, producing a greater thickness ot' glass at that point.

When the jacket is placed over the thermometer-tube it should be of sutlicient length to extend below the scale marked thereon,and the jacket may be secured by any suitable cement to the tube, so that the rounded protuberance B will be coincident with or opposite the front of the tube A. It will be sufficient to apply this cement only at the lower end of the jacket.

The magnifying properties ot' the lens-like protuberance B enable the mercury or fluid in the bore to be very easily seen, and the jacket forms a protection to the tube and prevents the black on the engraved scale from being defaced by the hands, as the hands do not come in contact with the part of the tube upon which is the scale.

The jacket is very desirable, inasmuch as it can be applied to tl1ermometertubes already made.

What I claim as my invention, and desire to secure by Letters Patent, is-

1. A glass jacket fora thermometer-tube having a greater thickness upon one side, so as to form a legs-like protubtganpe upon the exterior, substantially as and for the purpose specified.

2. The combination, with a thermometertube, of a glass jacket having a lens-like protuberance upon its exterior, and secured outside said tube with said protuberance opposite the front ofthe said tube, substantially as and for the purpose specified.

JOHN BARRY.

Witnesses:

FEEDK. HAYNEs, RoBT. ARCHIBALD. 

